I'll prove it (DenNor fic)

(Human AU)
Mathias Køhler is an average high school teenager. He's got friends, a small family, talent, what else could a teenager want? Well, it turns out Mathias had a few secrets. Those friends? They constantly insult him, that family? His dad's a drunk that constantly beats him up. That talent? He's only good at writing, what good is that for an actual career? The worst part is, he also has a huge crush on his best friend, Lukas Hansen, but Lukas defiantly doesn't feel the same. Pushed to the edge,a this can't take it and decides to end his life. Before he can pull the trigger a mysterious women stops him. She pleads for him to stop and claims herself as his "guardian angel." She makes a deal with Mathias, if she can prove to him that he is loved and wanted in 30 days, he'll keep his life. If not, then he's free to end it.

Will this women prove a point to Mathias? Or will it be too late to help?